Carbuff, that sucks but of course I'm not surprised. Were you driving through puddles or was it raining just before the wrench appeared?
I'm curious if your dealer installed a "spray shield" as part of the recall fixes. My dealer claimed that "all the recall work has been performed" but this shield is NOT on my car and I think that's the problem.
Here's a picture from another FFE that had the recall work done, including this thin black plastic shield to protect the HV battery connectors behind the rear driver's side wheel. If you squat down and look underneath just in front of the rear tire, you should be able to see the orange connectors and (hopefully) see if this black shield is in there partly covering them up: